Detecting At-Risk Alzheimer's Disease Cases

While APOEɛ4 is the major genetic risk factor for Alzheimer's disease (AD), amyloid dysmetabolism is an initial or early event predicting clinical disease and is an important focus for secondary intervention trials. To improve identification of cases with increased AD risk, we evaluated recruitment procedures using pathological CSF concentrations of Aβ42 (pAβ) and APOEɛ4 as risk markers in a multi-center study in Norway. In total, 490 subjects aged 40-80 y were included after response to advertisements and media coverage or memory clinics referrals. Controls (n = 164) were classified as normal controls without first-degree relatives with dementia (NC), normal controls with first-degree relatives with dementia (NCFD), or controls scoring below norms on cognitive screening. Patients (n = 301) were classified as subjective cognitive decline or mild cognitive impairment. Subjects underwent a clinical and cognitive examination and MRI according to standardized protocols. Core biomarkers in CSF from 411 and APOE genotype from 445 subjects were obtained. Cases (both self-referrals (n = 180) and memory clinics referrals (n = 87)) had increased fractions of pAβ and APOEɛ4 frequency compared to NC. Also, NCFD had higher APOEɛ4 frequencies without increased fraction of pAβ compared to NC, and cases recruited from memory clinics had higher fractions of pAβ and APOEɛ4 frequency than self-referred. This study shows that memory clinic referrals are pAβ enriched, whereas self-referred and NCFD cases more frequently are pAβ negative but at risk (APOEɛ4 positive), suitable for primary intervention.

Lateral extra-articular knee reconstruction: long-term patient outcome and satisfaction

Fifty-two patients who had an extraarticular reconstruction for anterior cruciate ligament (ACL) insufficiency were interviewed at an average of 11.4 years after their reconstruction. During the follow-up period, 4 patients (8%) had intra-articular reconstructions for persistent instability or re-injury, and another 4 (8%) had arthroscopic surgery for meniscal lesions. The mean Lysholm score at follow-up was 76.9. Of the 52 patients, 5 had had subsequent surgery during the follow-up period. In the remaining 47 patients, the results were excellent in 14 (29%), good in 10 (23%), fair in 7 (15%), and poor in 16 (33%). Patients operated on acutely (<6 weeks after injury) had a mean score of 82, whereas patients operated on more than 6 weeks after injury had a mean score of 75. Adding those patients who required subsequent reconstructions for persistent instability (4 knees) and those who obtained fair and poor results yielded an alarming rate of unsatisfactory results (52%). On the basis of these findings, we believe the lateral extraarticular reconstruction is not an acceptable form of treatment for the functionally unstable knee.

An analysis of sports knee evaluation instruments

This study examined four commonly used sports knee evaluation instruments to establish normative data. A total of 91 volunteers who had not sought treatment for knee pain or any other knee complaint at any time in the past underwent a detailed medical history and examination of both of their knees. Three numerical systems (Feagin and Blake Knee Score, Lysholm Knee Score, and the Hospital for Special Surgery Knee Disability Assessment) and one nonnumerical system (the International Knee Documentation Committee Quick Knee Profile) were evaluated. A significant difference in the proportion of knees with excellent/normal ratings was seen among the four evaluation systems (P<.0001): Hospital for Special Surgery Knee Disability Assessment, 99.5%; Feagin and Blake Knee Score, 84.6%; Lysholm Knee Score, 84.1%; and the International Knee Documentation Committee Quick Knee Profile, 50.5%. Results showed that three objective component scores for the International Knee Documentation Quick Knee Profile were significantly lower than all other component scores (P<.05). These components included: overall ligament examination, Lachman, and total AP translation. These data may be useful as a baseline by which investigators studying patients following knee reconstructive procedures have a basis for comparison of their results.

Bilateral pathologic fractures in a patient with beta-thalassemia undergoing total hip arthroplasty

A 49-year-old woman with beta-thalassemia minor and degenerative joint disease underwent bilateral hybrid total hip arthroplasty. Postoperative radiographs showed bilateral femoral shaft fractures extending distal to the cement plug. Examples of the hemodynamic complications of beta-thalassemia have been reported in the literature; however, this particular orthopaedic complication has not been reported before.

An analysis of Food and Drug Administration medical device reports relating to total joint components

A total of 1,717 total hip and 2,769 total knee medical device reports submitted to the U.S. Food and Drug Administration (FDA) from 1984 through 1993 were reviewed. A large percentage of total hip complications could be attributed to some aspect of component modularity. Cementless modular acetabular components were the single largest source of device-related complications. Fifty-six percent of total knee medical device reports (MDRs) were associated with accelerated polyethylene wear. By location, MDRs identified patellar (46%), tibial (33%), and femoral (5%) component complications. It was estimated that less than 5% of device-related complications were reported to the FDA. Based on the reports received, it was apparent that mechanical failure of components was a common and increasing cause of total joint revision.